Downlink refers to connections from a transmitting station to a receiving station. The decisive factor here is direction. The starting point is a sending station, the end point is the receiving station.
A downlink is used to transfer larger volumes of data between these two stations in the direction of the receiving station. The download of a larger file is referred to as a download. The term downlink comes from mobile communications and satellite technology. Downlink refers to the downlink, the radio link from the transmitter to the user.
In satellite transmission, it is the transmission from the satellite to the receiving ground station, and in mobile communications, it is the transmission from the base station to the cell phones. The opposite direction of transmission is called the uplink or uplink.